A watchdog timer is a computer hardware timing device that triggers a system reset if the main program, due to some fault condition, such as a hang, neglects to regularly service the watchdog (writing a “service pulse” to it, also referred to as “petting the dog”). The intention is to bring the system back from the hung state into normal operation. Such a timer has got various important applications, one of them being in ATMs (Automated Teller Machine) which we have studied and designed in our project
